Abstract:

Carbon storages and distribution in three patterns of poplar-crop intercropping patterns were studied with a biomass measurement method in the North of Jiangsu Province. The results indicated that total soil carbon in 100 cm ranged from 0.64 to 15.27 g·kg^-1. For the three patterns, soil carbon storage of K, P and W patterns was 71.19, 40.67 and 42.64 t·hm^-2 respectively. There was a significant difference in carbon density between fine roots and other components of the poplar, but carbon storage in poplar stem ranked first compared with other poplar components. Carbon density in roots of corps was significantly lower than that of other components of the crops investigated, and the carbon storage in the harvested parts (ears or pods) was higher than that of the other parts, accounting for about around 50% for wheat, maize and bean, while around 45% for rice. However, the highest carbon storage of the crops was observed in the annual cropping system of wheat+corn among three poplar intercropping patterns. The annual carbon return in litterfall was (0.78±0.23)，(0.73±0.22) and (0.37±0.09)t·hm^-2a^-1 respectively for K, W and P pattern. Carbon storage in poplar-crop intercropping ecosystem for the three patterns was in an order of K pattern＞W pattern＞ P pattern, while the carbon storage in the various parts of the agroforestry system was soil＞crop＞poplar＞litterfall for all the three poplar-crop intercropping patterns.

Key words: poplar, agroforestry ecosystem, biomass, soil organic carbon, carbon storage